Enable to listen to WindowContext's config changes

This CL overrides registerComponentCallbacks for
WindowContext. Users can use below code snippet
to listen to Configuration changes.
```
Context windowContext = context.createWindowContext(
        display, ...);
windowContext.registerComponentCallbacks(
        new ComponentCallbacks() {
            @Override
            public void onConfigurationChanged(
                    Configuration newConfig) {
                    // Do Something
                }
        });
```

Bug: 181134729
Test: atest WindowContextTests
Test: atest ComponentCallbacksControllerTest

Change-Id: Iff46607bae3c942a96b64dcc97708f3a8c33f23a